Neutron dose assessment method and device based on blood sodium 24 specific activity

Abstract

The present invention relates to the field of nuclear emergency medical rescue, and provides a neutron dose assessment method and device based on blood sodium 24 specific activity. The blood sodium 24 specific activity-neutron dose conversion coefficient is calculated in advance through a human body digital model. When assessing the neutron dose received by the human body, it is only necessary to measure the sodium 24 characteristic gamma ray counts in the blood sample of the tested person, and finally the neutron dose received by the person is assessed using the measured blood sodium 24 specific activity and the blood sodium 24 specific activity-neutron dose conversion coefficient calculated in advance. Compared with the traditional method, the present invention greatly improves the neutron dose test efficiency and further improves the test accuracy.

Description

[0001] This application claims the priority of the Chinese invention patent application filed with the China Patent Office on April 27, 2023, with application number 202310464319.9 and invention name “Portable Neutron Dosimeter”, the entire contents of which are incorporated by reference in this application. Technical Field

[0002] The invention relates to the field of nuclear emergency medical rescue, and relates to a neutron dose assessment method and device based on blood sodium 24 specific activity. Background Art

[0003] In nuclear explosions and nuclear accidents, neutrons are an important source of radiation for human external irradiation. When people are exposed to neutron external irradiation, the severity of their radiation damage and secondary illness is closely related to the neutron dose they received at the time; therefore, timely and accurate assessment of neutron doses is of great value for the medical treatment of the injured and the assessment of the degree of hazard of the accident. Especially in the scenario of a nuclear disaster, a large number of people are exposed to neutron external irradiation. It is necessary to complete the assessment of the severity of neutron external irradiation for a large number of people in the shortest possible time, and then carry out targeted treatment according to the severity of the assessment, so as to achieve the purpose of scientific treatment, allocate medical resources on demand, and avoid the occurrence of medical resource runs.

[0004] When a person is exposed to neutrons, the neutrons will undergo a radiation capture reaction with the sodium-23 element in the human body to produce sodium-24. The reaction formula is:

[0005] n+ 23 Na→ 24 Na

[0006] Sodium-24 is a radioactive nuclide that produces beta - Decay and produce characteristic gamma rays, the two strongest characteristic gamma rays have energies of 1369keV and 2754keV. Human blood is distributed throughout the body and circulates continuously to exchange sodium 24 with other body fluids, so the sodium 24 in the blood can be considered to be evenly distributed. The specific activity of sodium 24 in the blood is positively correlated with the neutron dose received by the human body, so by sampling the blood of the irradiated person and measuring the sodium 24 specific activity of the blood sample, the neutron dose can be evaluated.

[0007] In the prior art, there are the following disadvantages in sampling a small amount of blood from the irradiated person and measuring the sodium 24 specific activity of the blood sample: 1. Since the amount of human blood sampled should not be too much and the sodium 24 specific activity in the blood is low, in order to ensure that sufficient sodium 24 characteristic gamma ray counts are obtained, it is often necessary to measure for more than 1 hour, that is, the measurement technology requires high professionalism and takes a long time; 2. Too long a measurement time will introduce interference with the environmental background radiation count. Usually, professionals in this field will add a lead shielding layer to the detector to shield the environmental background radiation, but lead contains trace amounts of radioactive nuclides, such as 208 The characteristic gamma ray 2615keV produced by Tl decay will interfere with the characteristic gamma ray 2754keV of sodium 24, so a large amount of lead shielding is not conducive to the measurement of blood sodium 24 activity. 3. In the prior art, even if the sodium 24 specific activity of the blood sample is measured, it is still necessary to obtain the single collision dose produced by the unit flux of neutrons, the probability of neutrons with energy E being captured in the body, and the neutron energy distribution. The neutron dose can only be determined by the relative value of , and the measurement procedure is still complicated.

[0008] Therefore, there is an urgent need for a neutron dose assessment method based on blood sodium 24 specific activity with high measurement efficiency and accuracy. Summary of the invention

[0009] The present invention provides a neutron dose assessment method, device and electronic equipment based on blood sodium 24 specific activity to solve at least one problem existing in the prior art.

[0010] To achieve the above object, the present invention provides a neutron dose assessment method based on blood sodium 24 specific activity, the method comprising:

[0011] Obtaining blood and physical data of the tested person; wherein the physical data includes the height and weight of the tested person;

[0012] Detecting the blood by a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the tested person, and then determining the blood sodium 24 specific activity;

[0013] Based on the blood sodium 24 specific activity and the pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient, the neutron dose of the tested person is obtained; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the body data and irradiation data of the tested person using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry.

[0014] Further, preferably, the method for obtaining the blood sodium 24 specific activity-neutron dose conversion coefficient includes:

[0015] Using the preset human tomographic image data sets corresponding to different heights and weights, digital human models corresponding to different heights and weights are established;

[0016] Obtain the number of pixels and density value of each organ tissue of the human digital model corresponding to the preset height and weight, and then obtain the blood tissue quality;

[0017] Based on blood tissue 23 The Na mass percentage, blood tissue mass and Avogadro constant are used to obtain the blood tissue mass in the human digital model corresponding to the preset height and weight. 23 The number of Na atoms;

[0018] The particle transport simulation program was used to simulate the human body digital model with preset height and weight, based on the blood tissue quality and blood tissue 23 The number of Na atoms obtains the neutron dose and blood sodium 24 specific activity corresponding to the preset neutron energy and neutron irradiation geometry;

[0019] According to the neutron dose and the blood sodium 24 specific activity, a blood sodium 24 specific activity-neutron dose conversion coefficient is obtained.

[0020] Further, preferably, the blood is tested by a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the tested person, and then the blood sodium 24 specific activity A is determined. S , achieved by:

[0021]

[0022] Wherein, X0 is the characteristic gamma ray count of sodium 24 in the blood sample of the tested person obtained by testing the blood with a neutron dosimeter, and λ is the decay constant of sodium 24, λ≈1.2836×10 -5 ; ε is the detection efficiency of the detector, ε≈12.34%; I is the branching ratio of the characteristic gamma ray of sodium 24, I≈100%; t is the measurement time, t=600s, the specific activity of sodium 24 A S , unit is Bq / g.

[0023] Further, preferably, it also includes a specific activity A of blood sodium 24 S Perform individual blood sodium content correction and obtain the blood sodium 24 specific activity A after sodium content correction using the following formula C ;

[0024] A c =A s ×S n / S s

[0025] Among them, S nis the blood sodium content value used in the human digital model corresponding to the preset height and weight, S s It is the actual blood sodium content of the tested person.

[0026] Furthermore, preferably, the method further includes performing time difference correction on the neutron dose of the tested person, and obtaining the neutron dose G of the tested person after time difference correction by the following formula: s ;

[0027] G s =A c ×L n (E, K) × T c

[0028] Among them, T c is the time correction factor; L n (E, K) is the blood sodium 24 specific activity-neutron dose conversion coefficient; A C The specific activity of blood sodium 24 after correction for sodium content; T = 14.12h, t0-t1 is the time difference between the occurrence of neutron irradiation and the measurement of sodium 24 activity in the blood of the tested person.

[0029] Further, preferably, the neutron dose G corresponding to the preset neutron energy and the neutron irradiation geometry is obtained by using a human digital model corresponding to a preset height and weight. n (E, K) is achieved by the following formula:

[0030]

[0031] Among them, D n,t (E,K) represents a human digital model H with a single neutron of neutron energy E and irradiation method K. n (h,w) Organ O n,t The deposited energy in is in J; M n,t For organ O n,t The mass of , in g, K∈(LLAT, RLAT, AP, PA, ISO, ROT).

[0032] Further, preferably, a particle transport simulation program is used to obtain a blood sodium 24 specific activity A corresponding to a preset neutron energy and a neutron irradiation geometry through a human digital model corresponding to a preset height and weight. n The method of (E, K) comprises:

[0033] A n (E, K) = F n (E, K, ε)×σ(ε)×B n (h,w) / M n,1

[0034] Among them, F n (E, K, ε) represents the human body digital model H n (h,w) is the neutron fluence in the blood under the irradiation condition of a single neutron with energy E and irradiation geometry K, ε is the neutron energy reaching the blood after slowing down; σ(ε) is the difference between the neutron with energy ε and the blood 23 The cross section of Na capture reaction; B n (h,w) represents the human body digital model H n The number of atoms of blood sodium 23 in (h,w); M n,1 Human body digital model H n (h,w) blood tissue mass.

[0035] In order to solve the above problems, the present invention also provides a neutron dosimeter, which is applied to the neutron dose assessment method based on blood sodium 24 specific activity. The neutron dosimeter includes:

[0036] It comprises a test tube for holding a blood sample, a detection unit for testing the neutron dose of the blood sample in the test tube, and a shielding shell; wherein,

[0037] The detection unit includes a detection crystal module and a photoelectric conversion module arranged below the detection crystal module; a deep well portion for accommodating the test tube is arranged in the middle of the detection crystal module;

[0038] The detection unit and the test tube are arranged in a shielding chamber of the shielding shell.

[0039] In order to solve the above problems, the present invention also provides a neutron dose assessment device based on blood sodium 24 specific activity, the device comprising:

[0040] A test data acquisition unit, used to acquire blood and body data of the test person; wherein the body data includes the height and weight of the test person;

[0041] A specific activity measurement unit, used to detect blood through a neutron dosimeter to obtain sodium 24 characteristic gamma ray counts in the blood sample of the tested person, and then determine the blood sodium 24 specific activity;

[0042] A neutron dose acquisition unit is used to obtain the neutron dose of the subject based on the blood sodium 24 specific activity and the pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the body data and irradiation data of the subject using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry.

[0043] In order to solve the above problem, the present invention further provides an electronic device, the electronic device comprising:

[0044] at least one processor; and,

[0045] a memory communicatively connected to the at least one processor; wherein,

[0046] The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the steps in the above-mentioned neutron dose assessment method based on blood sodium 24 specific activity.

[0047] The neutron dose assessment method, device and electronic device based on blood sodium 24 specific activity of the present invention have the following beneficial effects:

[0048] 1) Since the conversion calculation of blood sodium 24 specific activity to neutron dose has been carried out in advance based on the human body digital model, when evaluating the neutron dose to the human body, it is only necessary to use the neutron dosimeter to measure the blood sodium 24 specific activity to calculate the neutron dose to the human body. 24 The specific activity of Na can be measured; the neutron dose of a person can be determined; compared with the traditional method, the present invention greatly saves the time of neutron dose assessment, and is particularly suitable for the scenario where a large number of people need to undergo neutron dose assessment and screening after a nuclear disaster;

[0049] 2) The neutron dose assessment method of the present invention is quick and convenient, which is reflected in the simple functions of the neutron dosimeter, which can be operated by non-professionals. Therefore, a large number of personnel can be deployed to carry out neutron dose assessment and screening. Compared with the traditional method that requires professional operation, this method realizes high-throughput screening and greatly improves the efficiency of neutron dose measurement, which has very important social and economic benefits.

[0050] 3) The present invention provides a semi-automatic neutron dose measurement method, which only requires manual collection of a certain amount of blood from the subject. 24 The specific activity of Na is then measured in human blood 24 After the specific activity of Na, the physical data of the test person and the irradiation data are obtained and input, the neutron dose measurement data of the test person can be obtained, which has the technical effect of efficiently completing the neutron dose measurement; in addition, the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the height, weight, neutron energy spectrum and irradiation geometric conditions of the test person using a digital human body model, therefore, the accuracy of neutron dose measurement is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic flow chart of a neutron dose assessment method based on blood sodium 24 specific activity provided by one embodiment of the present invention;

[0052] Figure 2 A schematic diagram of the structure of a neutron dosimeter provided in one embodiment of the present invention;

[0053] Figure 3 A schematic diagram of the principle of a neutron dose assessment device based on blood sodium 24 specific activity provided by an embodiment of the present invention;

[0054] Figure 4 A schematic diagram of the structure of a neutron dose assessment device based on blood sodium 24 specific activity provided by an embodiment of the present invention;

[0055] Figure 5 A schematic diagram of the internal structure of an electronic device for implementing a neutron dose assessment method based on blood sodium 24 specific activity provided by an embodiment of the present invention.

[0056] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0057] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0058] Reference Figure 1 FIG. 1 is a flow chart of a method for evaluating neutron dose based on blood sodium 24 specific activity provided by an embodiment of the present invention. The method can be performed by a device, which can be implemented by software and / or hardware.

[0059] In this embodiment, the neutron dose assessment method based on blood sodium 24 specific activity includes steps S110 to S130.

[0060] S110, obtaining blood and physical data of the tested person; wherein the physical data includes the height and weight of the tested person.

[0061] The test person is a person who needs to undergo neutron dose detection after being exposed to nuclear radiation. In the prior art, when evaluating the neutron dose by the blood sodium 24 specific activity, the serious impact of the difference in body fat thickness (i.e., the same height but different weight) on the blood sodium 24 specific activity is not considered, that is, since the height and weight directly affect the blood sodium 24 specific activity and the neutron dose, and then affect the blood sodium 24 specific activity-neutron dose conversion relationship; therefore, it is necessary to obtain the actual height and weight of the test person, and then obtain the corresponding human digital model based on the height and weight of the test person, so that the neutron dose assessment is more accurate. In the specific implementation process, if the height and weight of the test person are not completely consistent with the height and weight of the human digital model, the weight of the human digital model that is closest to the weight of the test person can be directly input without considering the height.

[0062] S120, detecting the blood by a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the tested person, and then determining the blood sodium 24 specific activity.

[0063] The present invention also provides a neutron dose meter, which is applied to the neutron dose assessment method based on the blood sodium 24 specific activity. Figure 2 A schematic diagram of the structure of a neutron dosimeter provided in one embodiment of the present invention; Figure 3 for Figure 2 A top view of Figure 2 and Figure 3 As shown, the neutron dosimeter is a scintillation spectrometer, including a test tube 101 for holding a blood sample, a detection unit for testing the neutron dose of the blood sample in the test tube 101, and a shielding shell. Specifically, the detection result of the detection unit is the characteristic gamma ray count X0 of blood sodium 24. The detection unit includes a detection crystal module 102 and a photoelectric conversion module 105 arranged below the detection crystal module 102; a deep well portion for accommodating the test tube 101 is arranged in the middle of the detection crystal module 102; the detection unit and the test tube 101 are arranged in a shielding chamber of the shielding shell. The shielding shell includes an inner shielding layer 103 and an outer shielding layer 104, and the outer shielding layer 104 is wrapped around the outer side of the inner shielding layer 103. The test tube 101 is 80 mm long, 18 mm in outer diameter, 1 mm thick, and has a hemispherical bottom, and the volume of the blood sample is 10 mL. The geometric design of the radiation detection unit and the test tube 101 for holding the blood sample is as follows: the test tube 101 is 80 mm long, 18 mm in outer diameter, 1 mm in wall thickness, and has a hemispherical bottom. The volume of the blood sample is 10 mL. The detection crystal module 102 of the detection unit is a cylindrical NaI (Tl) crystal with a diameter of 75 mm and a height of 75 mm. A cylindrical deep well is dug in the center of the circular surface of the detection crystal module. The deep well has a diameter of 18 mm and a depth of 65 mm for inserting the test tube. The inner shielding layer 103 is an electrolytic copper part. The outer shielding layer 104 in the shielding shell is a cylindrical old lead shell with an outer diameter of 16 cm, an outer height of 35 cm, and a thickness of 2 cm. The inner shielding layer 103 is a cylindrical electrolytic copper shell with an outer diameter of 12 cm, an outer height of 31 cm, and a thickness of 2 cm.

[0064] Specifically, 10 mL of the venous blood sample of the tested person is taken and placed in a test tube 101 , and the test tube 101 is placed in the cylindrical deep well of the detection crystal module 102 , and the measurement is performed for 10 minutes to obtain the characteristic gamma ray count X0 of the blood sodium 24 .

[0065] The blood is tested by a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the tested person, and then the blood sodium 24 specific activity A is determined. S , achieved by:

[0066]

[0067] Wherein, X0 is the characteristic gamma ray count of sodium 24 in the blood sample of the tested person obtained by testing the blood with a neutron dosimeter, and λ is the decay constant of sodium 24, λ≈1.2836×10 -5 ; ε is the detection efficiency of the detector, ε≈12.34%; I is the branching ratio of the characteristic gamma ray of sodium 24, I≈100%; t is the measurement time, t=600s, the specific activity of sodium 24 A S , unit is Bq / g.

[0068] That is to say, compared with the prior art, even if the blood sodium 24 specific activity of the blood sample is measured, it is still necessary to obtain the single collision dose generated by the neutron per unit flux, the probability of neutrons with energy E being captured in the body, and the neutron energy distribution. The relative value of can determine the neutron dose; the present invention only measures the blood of the tested person by a neutron dosimeter to obtain the characteristic gamma ray count X0 of blood sodium 24, and then obtains the blood sodium 24 specific activity A based on the above formula S . Greatly improved the detection efficiency of neutron dose.

[0069] S130. Obtaining the neutron dose of the tested person based on the blood sodium 24 specific activity and a pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the body data and irradiation data of the tested person using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry.

[0070] In a specific embodiment, the method for obtaining the blood sodium 24 specific activity-neutron dose conversion coefficient includes steps S131-S135.

[0071] S131, using the preset human tomographic image data set corresponding to different heights and weights to establish human digital models corresponding to different heights and weights. That is, to establish a human digital model set H of different heights and weights. n (h,w), where h is the height of the human digital model, w is the weight of the human digital model, and n∈(1,2,3…) is the number of the human digital model, representing a series of human digital models of different heights and weights.

[0072] Specifically, the method for building a human digital model corresponding to different heights and weights includes the following steps.

[0073] S1311, establish a human digital model set H of different heights and weights n(h, w), where h is the height of the human digital model, w is the weight of the human digital model, and n∈(1,2,3…) is the human digital model number, representing a series of human digital models of different heights and weights; that is, it is necessary to use a preset human tomographic image data set to establish a human digital model to represent the population exposed to external neutron radiation. The human tomographic image data set includes the human serial tomographic image. The prior art has disclosed the process of building a human digital model, preprocessing the serial tomographic images of the human body, and then generating a three-dimensional digital model. The digital model can be a voxel model, etc.; it can be processed by, but not limited to, Matlab7.0 and Photoshop8.0 image processing software to process the human serial tomographic images.

[0074] However, the human digital models in the prior art are all built based on standard height and weight. Their accuracy cannot meet the requirements of the present invention. Therefore, the present invention needs to obtain a large number of human tomographic image data sets corresponding to height and weight; in the specific implementation process, because the fat thickness of men and women with the same height and weight is also different, therefore, when building a human digital model, gender factors can also be considered and gender can also be used as a variable.

[0075] S1312, using human tomographic image dataset U of different heights and weights n (h,w) to build a human digital model H n (h,w). n (h,w) represents a human tomographic image dataset with a height of h and a weight of w. n∈(1,2,3…) is the number of the tomographic dataset, representing a series of human tomographic image datasets with different heights and weights.

[0076] S1313, for the tomographic image data set U n Each tomographic image in (h,w) is used to identify and segment the organ tissue, and different colors I n,t (R, G, B) represent different organs and tissues n,t . Among them O n,t， Represents the tth organ or tissue in the nth tomographic image data set, t∈(1,2,3…T), the maximum value of t is T, indicating that there are T organs or tissues in total. n,t (R, G, B) represents the color value of the t-th organ in the n-th tomographic image data set, and 0≤R≤255, 0≤G≤255, 0≤B≤255.

[0077] S1314. Identify the segmented organ tissues; wherein the organ tissues include at least blood, heart, lungs, liver, kidneys, skin, bones, stomach, intestines, muscles, etc.

[0078] S1315, to Un After the organ tissue recognition is performed on the (h,w) tomographic image dataset, a new tomographic image dataset C is formed. n (h,w), n∈(1,2,3…).

[0079] S1316, for C n The (h,w) tomographic image dataset is assigned with human element composition and density values. The method is to assign a tomographic dataset C n (h, w), respectively for each identified and segmented organ tissue O n,t , assign element composition and density value P n,t {(c1,r1),(c2,r2),(c3,r3),…(c i ,r i ),ρ n,t}, where t∈(1,2,3…T); c i Represents a chemical element, r i It represents the mass percentage of the chemical element, and r1+r2+r3…+r i =1;ρ n,t Indicates an organ or tissue n,t Density in g cm -3 .

[0080] For example, for the second tissue-fat in the fifth tomographic image data set, its element composition and density value are expressed as: 5,2 {(C, 33%), (H, 44%), (O, 20%), (N, 3%), 1.04}, indicating fat O 5,2 It is composed of 33% carbon, 44% hydrogen, 20% oxygen, and 3% nitrogen, and its density is ρ. 5,2 =1.04 g cm -3 For example, the physical properties of the first muscle tissue in the third tomographic image dataset are: 3,1 {(C, 32%), (H, 45%), (O, 22%), (N, 1%)}, ​​its density value is ρ3,1=1.04g cm -3 ; The element composition and density values ​​of the human body digital model are taken from the International Commission on Radiation Units and Measurements (ICRU) 44 and ICRU 46 reports. S1317, C n After the element composition and density value assignment of the (h,w) tomographic image data set, the human body digital model H is established. n (h,w), n∈(1,2,3…).

[0081] S132, obtaining the pixel number and density value of each organ tissue of the human digital model corresponding to the preset height and weight, and then obtaining the blood tissue mass. That is, calculating the human digital model H n The mass M of all organs of (h,w) n,t . M n,t Represents the nth human digital model H n The mass of the tth organ in (h,w).

[0082] Specifically, M n,t =V n,t ×Z n,t ×ρ n,t , t∈(1,2,3…T). Where V n,t Represents the nth human digital model H n (h,w) Organ tissue O n,t The volume of a small cube in cm 3 . V n,t It is determined by the pixel resolution of the tomographic image used (i.e., the size of each pixel, such as the resolution of the tomographic image is 0.5 mm × 0.5 mm) and the distance between two adjacent tomographic images (e.g., the distance between two adjacent tomographic images is 1 mm, then V n,t The volume size is 0.5mm×0.5mm×1mm=0.00025cm 3 );Z n,t For organ tissue O n,t The number of small and medium cubes, whose value is the number of slice images C to be read. n All color values ​​in (h,w) are I n,t (R, G, B) pixels are obtained by accumulating the number of pixels; ρ n,t For organ tissue O n,t Density value. For example, the blood tissue in the nth human body digital model is represented by O n,1 Indicates that its color value is I n,1 (23,100,239), human body model H n The color value in (h,w) is I n,1 The cumulative sum of all pixel numbers at (23,100,239) is 20,000,000, and the blood density ρ n,1 =1.01 g cm -3 , then the human body model H n (h,w) The blood mass of the whole body M n,1 It is 0.00025×20000000×1.01=5050g.

[0083] S133, according to blood tissue 23The Na mass percentage, blood tissue mass and Avogadro constant are used to obtain the blood tissue mass in the human digital model corresponding to the preset height and weight. 23 The number of Na atoms. That is, calculate the human body digital model H n The number of atoms of blood sodium 23 in (h,w) B n (h,w).

[0084] Specifically, according to the human body digital model H n The mass percentage of sodium 23 in blood tissue in (h,w) S n 、Blood tissue quality M n,1 and Avogadro's constant N A , calculate the blood volume of the human digital model 23 The number of Na atoms n (h,w), n∈(1,2,3…). Among them, B n (h,w)=M n,1 ×S n / 23×N A .

[0085] S134, using a particle transport simulation program, by presetting a human digital model corresponding to height and weight, based on blood tissue quality and blood tissue 23 The number of Na atoms is used to obtain the neutron dose and blood sodium 24 specific activity corresponding to the preset neutron energy and neutron irradiation geometry; that is, the particle transport simulation program is used to calculate the human body digital model H n (h,w) Neutron dose G under different single neutron energies and different irradiation geometries n (E, K). n (E, K) represents a single neutron with neutron energy E and irradiation geometry K, and a human digital model H n The neutron dose of (h,w) is given by K∈(LLAT, RLAT, AP, PA, ISO, ROT), where LLAT, RLAT, AP, PA, ISO, ROT represent left-side irradiation, right-side irradiation, front-to-back irradiation, back-to-front irradiation, isotropic irradiation, and rotational irradiation, respectively.

[0086] The neutron dose G corresponding to the preset neutron energy and neutron irradiation geometry is obtained through the human body digital model corresponding to the preset height and weight. n (E, K) is achieved by the following formula:

[0087]

[0088] Among them, D n,t (E,K) represents a human digital model H with a single neutron of neutron energy E and irradiation method K. n (h,w) Organ On,t The deposited energy in J; M n,t For organ O n,t The mass of the human body is expressed in g, K∈(LLAT, RLAT, AP, PA, ISO, ROT). The energy deposition value D of each organ of the human body digital model under different particle energies E and different irradiation geometric conditions K is calculated using particle transport simulation software. n,t (E, K); where n∈(1, 2, 3…T), T is the total number of organs; K∈(LLAT, RLAT, AP, PA, ISO, ROT), LLAT, RLAT, AP, PA, ISO, ROT represent left irradiation, right irradiation, front-to-back irradiation, back-to-front irradiation, isotropic irradiation, and rotational irradiation, respectively.

[0089] Calculation of the human body digital model H using a particle transport simulation program n (h,w) Blood sodium 24 specific activity A under different single neutron energies and different irradiation geometric modes n (E, K). n (E, K) represents a single neutron with energy E and irradiation geometry K on a human digital model H n Blood sodium 24 specific activity in (h,w), where K∈(LLAT, RLAT, AP, PA, ISO, ROT), LLAT, RLAT, AP, PA, ISO, ROT represent left irradiation, right irradiation, anterior-posterior irradiation, anterior-posterior irradiation, isotropic irradiation, and rotational irradiation, respectively.

[0090] Using the particle transport simulation program, the human digital model corresponding to the preset height and weight is used to obtain the blood sodium 24 specific activity A corresponding to the preset neutron energy and neutron irradiation geometry. n The method of (E, K) includes: n (E, K) = F n (E, K, ε)×σ(ε)×B n (h,w) / M n,1 Among them, F n (E, K, ε) represents the human body digital model H n (h,w) is the neutron fluence in the blood under the irradiation condition of a single neutron with energy E and irradiation geometry K, ε is the neutron energy reaching the blood after slowing down; σ(ε) is the difference between the neutron with energy ε and the blood 23 The cross section of Na capture reaction; B n (h,w) represents the human body digital model H n The number of atoms of blood sodium 23 in (h,w); M n,1 Human body digital model H n (h,w) blood mass.

[0091] Among them, the neutron fluence F in the blood of the human digital model is n (E, K, ε) is obtained by the following formula:

[0092] F n (E, K, ε) = J n / (R n ×P n )

[0093] That is, using the particle transport simulation program, the neutron flux F of a single neutron with energy E and different irradiation geometric modes in the blood tissue of the nth human digital model is calculated. n (E, K, ε); the path length of the neutron entering the blood tissue is divided by the volume of the blood tissue; K represents the neutron external irradiation geometry, K∈(LLAT, RLAT, AP, PA, ISO, ROT), E represents the initial monoenergetic neutron energy incident on the human body, ε represents the neutron energy of the initial monoenergetic neutron energy entering the blood tissue after being slowed down by other organs and tissues; J n represents the length of the neutron's motion track in the blood of the nth human digital model, R n represents the resolution of the nth human digital model, P n is the number of pixels of blood tissue in the nth human digital model. n The main idea of ​​(E, K, ε) is to track and record the movement of neutrons in the blood of the human digital model and calculate the length of the neutron movement track J in the blood tissue. n .

[0094] The length of the neutron's path in blood tissue is J n The specific method is: when the incident neutron i enters the boundary of blood tissue, the state of the neutron at this moment is recorded and represented by Par(i)(v0, t0), where v0 and t0 represent the initial velocity and initial time of the neutron entering the boundary of blood tissue respectively; when the neutron leaves the boundary of blood tissue, the state of the neutron at this moment is represented by Par′(i)(v′, t′), where v′ and t′ represent the departure velocity and departure time of the neutron respectively; the state of the neutron at any moment of its movement inside the blood tissue is represented by Par(i)(v, t).

[0095] Then J n The calculation method is:

[0096]

[0097] In the specific implementation process, the energy E of the initial monoenergetic neutron is set to 0.01, 0.015, 0.02, 0.03, 0.04, 0.05, 0.06, 0.08, 0.1, 0.15, 0.2, 0.3, 0.4, 0.5, 0.6, 0.8, 1, 2, 4, 6, 8, 10MeV, 11MeV, 12MeV, 13MeV, 14MeV, 15MeV, 16MeV, 17MeV, 18MeV, 19MeV, and 20MeV, respectively, to include common neutron energy ranges.

[0098] S135, according to the neutron dose and the blood sodium 24 specific activity, obtain the blood sodium 24 specific activity-neutron dose conversion coefficient. That is, calculate the human body digital model H n (h,w) Blood sodium 24 specific activity-neutron dose conversion coefficient L under different single neutron energies and different irradiation geometric modes n (E, K).

[0099] L n (E, K) = G n (E, K) / A n (E, K)

[0100] Among them, L n (E, K) represents the neutron dose per unit of blood sodium 24 specific activity.

[0101] As an improvement of this embodiment, in the prior art, when evaluating neutron dose by blood sodium 24 specific activity, the average neutron energy is often used for simplified calculation, without considering the neutron energy distribution, that is, the changes in blood sodium 24 specific activity and neutron dose caused by different neutron energies, and without considering the differences in blood sodium 24 specific activity and neutron dose caused by different irradiation geometries. Therefore, the present invention needs to obtain the blood sodium 24 specific activity-neutron dose conversion coefficient using a human body digital model according to the actual neutron energy E and irradiation geometry K.

[0102] Specifically, for neutron energy E, due to different neutron energies, the blood sodium 24 specific activity-neutron dose conversion coefficient is different, which will affect the accuracy of neutron dose assessment. Therefore, it is necessary to input neutron energy E into the measurement system based on neutron energy information obtained by measuring instruments, research and analysis, etc.

[0103] Specifically, for the irradiation geometry K, since the irradiation geometry affects the size of the blood sodium 24 specific activity-neutron dose conversion coefficient, it affects the accuracy of the neutron dose assessment. Therefore, it is necessary to determine the actual irradiation geometry of the exposed person through questioning, investigation, etc. Preferably, if the irradiation geometry of the exposed person during the irradiation period cannot be confirmed, the isotropic irradiation geometry can be input to approximately represent the actual irradiation geometry.

[0104] As an improvement of this embodiment, since the sodium content of human blood fluctuates between 135-145mmol / L, the sodium content of different people and the same person at different times fluctuates; however, in the prior art, when evaluating the neutron dose by the blood sodium 24 specific activity, the difference in blood induced sodium 24 production caused by the difference in individual blood sodium content is not taken into account. The blood sodium content of different individuals and the same individual at different times will vary due to physiological differences, eating habits, environmental influences and other factors, which will lead to differences in blood induced sodium 24 specific activity under the same neutron dose. Therefore, it is necessary to correct the blood sodium 24 specific activity according to the blood sodium content.

[0105] For the present invention, after correcting the deviation caused by the different blood sodium content of individuals, the blood sodium 24 specific activity of the tested person becomes A c .

[0106] A c =A s ×S n / S s

[0107] Among them, S n Human body digital model H n The blood sodium content value used in (h,w), S s It is the actual blood sodium content of the tested person.

[0108] As an improvement of this embodiment, there is a certain time difference between the occurrence of neutron irradiation and the measurement of sodium 24 activity of the personnel by blood drawing. The previous method only considered the reduction of blood sodium 24 due to radioactive decay during this period, and did not consider the changes in blood sodium 24 caused by human sodium metabolism. For the present invention, it also includes time difference correction of the neutron dose of the tested person. The radioactive half-life of sodium 24 is 15h, and the half-life of the retention time in the human body after a single intake of sodium is about 10 days. Therefore, after neutron irradiation of the human body, the total half-life of blood sodium 24 is T≈14.12h. The time point t0 when the tested person is irradiated and the time t1 when the specific activity of blood sodium 24 is measured are recorded to make time correction for the specific activity of blood sodium 24.

[0109] The neutron dose G of the tested person after time difference correction is obtained by the following formula: s .

[0110] G s =A c ×L n (E, K) × T c

[0111] Among them, T c is the time correction factor; L n(E, K) is the blood sodium 24 specific activity-neutron dose conversion coefficient; A C The specific activity of blood sodium 24 after correction for sodium content; T = 14.12h, t0-t1 is the time difference between the occurrence of neutron irradiation and the measurement of sodium 24 activity in the blood of the tested person.

[0112] In summary, after the above steps, the neutron dose G of the tested person is finally outputted, taking into account factors such as neutron energy, irradiation geometry, height and weight, individual differences in blood sodium 24 content, and measurement time. s

[0113] G s =A c ×L n (E, K) × T c

[0114] Among them, T c is the time correction factor.

[0115] In the specific implementation process, the present invention integrates various functions into one hardware and sets up a human-computer interaction system. It only needs to manually input the measured sodium 24 characteristic gamma ray count of the tested person, select the corresponding neutron energy and irradiation geometry, input the height and weight data of the tested person, input the irradiation time t0 and the start measurement time t1, and then the neutron dose G of the tested person can be output. s . The hardware data processing module automatically performs various calculations such as the calculation of the human blood sodium 24 specific activity-neutron dose conversion coefficient based on the human digital model, the sodium content correction of the blood sodium 24 specific activity, and the time difference correction of the neutron dose of the tested person. During the entire test process, the test system can not only display the test results on the human-computer interaction module, but also export the results to a file. Some test items can be analyzed and counted, that is, automatic comparison, automatic output of results and automatic statistical analysis are realized. It not only solves the problem of large amount of neutron dose detection data and long time-consuming detection results in the prior art; it further weakens the professional requirements of neutron detection for operators, and greatly improves the accuracy and efficiency of neutron dose measurement.

[0116] The neutron dose assessment method based on the blood sodium 24 specific activity of the present invention first calculates a series of human blood sodium 24 specific activity-neutron dose conversion coefficients based on human digital models of different heights and weights; then measures the sodium 24 characteristic gamma ray counts in the blood samples of the tested persons to obtain the blood sodium 24 specific activity of the tested persons; finally, the measured blood sodium 24 specific activity and the blood sodium 24 specific activity-neutron dose conversion coefficient calculated in advance are used to assess the neutron dose of the persons. The present invention takes into account the influence of human body weight, neutron energy spectrum, irradiation geometry, individual blood sodium content differences, sodium 24 radioactive decay and sodium element human metabolism on the accuracy of neutron dose assessment, thereby greatly improving the detection accuracy on the basis of ensuring the neutron detection efficiency. The present invention solves the problems of large uncertainty in neutron dose assessment based on human blood sodium-24 specific activity, low detection efficiency, long measurement time, environmental radiation interference, etc., and achieves the purpose of rapid neutron dose assessment using human blood sodium-24 specific activity, providing a new technical means for rapid dose diagnosis and classified treatment of large-scale populations in nuclear emergency scenarios.

[0117] like Figure 4 As shown, the present invention provides a neutron dose assessment device 400 based on the specific activity of blood sodium 24, which can be installed in an electronic device. According to the functions to be implemented, the neutron dose assessment device 400 based on the specific activity of blood sodium 24 can include a measured data acquisition unit 410, a specific activity measurement unit 420 and a neutron dose acquisition unit 430. The module described in the present invention can also be called a unit, which refers to a series of computer program segments that can be executed by an electronic device processor and can complete fixed functions, which are stored in the memory of the electronic device.

[0118] In this embodiment, the functions of each module / unit are as follows:

[0119] The test data acquisition unit 410 is used to acquire the blood and body data of the test person; wherein the body data includes the height and weight of the test person;

[0120] The specific activity measurement unit 420 is used to detect the blood through a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the tested person, and then determine the blood sodium 24 specific activity;

[0121] The neutron dose acquisition unit 430 is used to obtain the neutron dose of the subject based on the blood sodium 24 specific activity and the pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the body data and irradiation data of the subject using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry.

[0122] The neutron dose assessment device 400 based on the specific activity of blood sodium 24 of the present invention, on the one hand, takes into account the influence of human body weight, neutron energy spectrum, irradiation geometry, individual blood sodium content difference, sodium 24 radioactive decay and sodium element human metabolism on the accuracy of neutron dose assessment, thereby greatly improving the detection accuracy on the basis of ensuring the efficiency of neutron detection. On the other hand, based on the blood of the tested person, the sodium 24 characteristic gamma ray count in the blood sample of the tested person is obtained, and then the blood sodium 24 specific activity is determined, and then the neutron dose of the tested person is determined according to the human blood sodium 24 specific activity-neutron dose conversion coefficient. The present invention solves the problems of large uncertainty in neutron dose assessment based on human blood sodium 24 specific activity, low detection efficiency of blood sodium 24 specific activity measurement, long measurement time, and environmental radiation interference, and realizes the purpose of rapid neutron dose assessment using human blood sodium-24 specific activity, and provides a new technical means for rapid dose diagnosis and classification treatment of large-scale populations in nuclear emergency scenarios.

[0123] like Figure 5 As shown, the present invention provides an electronic device 5 for a neutron dose assessment method based on blood sodium 24 specific activity.

[0124] The electronic device 5 may include a processor 50 , a memory 51 , and a bus, and may also include a computer program stored in the memory 51 and executable on the processor 50 , such as a neutron dose assessment program 52 based on the specific activity of blood sodium 24 .

[0125] The memory 51 includes at least one type of readable storage medium, including flash memory, mobile hard disk, multimedia card, card-type memory (e.g., SD or DX memory, etc.), magnetic memory, disk, optical disk, etc. The memory 51 may be an internal storage unit of the electronic device 3 in some embodiments, such as a mobile hard disk of the electronic device 5. The memory 31 may also be an external storage device of the electronic device 5 in other embodiments, such as a plug-in mobile hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card, etc. equipped on the electronic device 3. Further, the memory 51 may also include both an internal storage unit of the electronic device 5 and an external storage device. The memory 51 may not only be used to store application software and various types of data installed in the electronic device 5, such as the code of a neutron dose assessment program based on the specific activity of blood sodium 24, but may also be used to temporarily store data that has been output or is to be output.

[0126] The processor 50 may be composed of an integrated circuit in some embodiments, for example, a single packaged integrated circuit, or a plurality of packaged integrated circuits with the same or different functions, including one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and combinations of various control chips, etc. The processor 50 is the control core (Control Unit) of the electronic device, and uses various interfaces and lines to connect various components of the entire electronic device, and executes or executes programs or modules stored in the memory 51 (such as a neutron dose assessment program based on blood sodium 24 specific activity, etc.), and calls data stored in the memory 51 to execute various functions of the electronic device 5 and process data.

[0127] The bus may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The bus is configured to realize connection and communication between the memory 51 and at least one processor 50, etc.

[0128] Figure 5 Only an electronic device with components is shown, and those skilled in the art will understand that Figure 5 The structure shown does not constitute a limitation on the electronic device 5, and may include fewer or more components than shown in the figure, or combine certain components, or arrange the components differently.

[0129] For example, although not shown, the electronic device 5 may also include a power source (such as a battery) for supplying power to each component. Preferably, the power source may be logically connected to the at least one processor 50 through a power management device, so that the power management device can realize functions such as charging management, discharging management, and power consumption management. The power source may also include any components such as one or more DC or AC power sources, recharging devices, power failure detection circuits, power converters or inverters, and power status indicators. The electronic device 3 may also include a variety of sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be repeated here.

[0130] Furthermore, the electronic device 5 may also include a network interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which is generally used to establish a communication connection between the electronic device 3 and other electronic devices.

[0131] Optionally, the electronic device 5 may also include a user interface, which may be a display, an input unit (such as a keyboard), or a standard wired interface or a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, and an OLED (Organic Light-Emitting Diode) touch device. The display may also be appropriately referred to as a display screen or a display unit, which is used to display information processed in the electronic device 5 and to display a visual user interface.

[0132] It should be understood that the embodiment is for illustration only and the scope of the patent application is not limited to this structure.

[0133] The neutron dose assessment program 52 based on the blood sodium 24 specific activity stored in the memory 51 in the electronic device 5 is a combination of multiple instructions. When running in the processor 50, it can achieve: obtaining the blood of the test person and the physical data of the test person; wherein the physical data includes the height and weight of the test person; detecting the blood by a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the test person, and then determining the blood sodium 24 specific activity; obtaining the neutron dose of the test person based on the blood sodium 24 specific activity and the pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the physical data and irradiation data of the test person using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry.

[0134] Specifically, the specific implementation method of the processor 50 for the above instructions can refer to Figure 1 The description of the relevant steps in the corresponding embodiment is not repeated here. It should be emphasized that in order to further ensure the privacy and security of the above-mentioned neutron dose assessment program based on the specific activity of blood sodium 24, the above-mentioned database can process data and store it in the node of the blockchain where the server cluster is located.

[0135] Furthermore, if the module / unit integrated in the electronic device 5 is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. The computer-readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM).

[0136] The embodiment of the present invention also provides a computer-readable storage medium, which can be non-volatile or volatile, and stores a computer program. When the computer program is executed by a processor, it is implemented as follows: obtaining the blood of the test person and the physical data of the test person; wherein the physical data includes the height and weight of the test person; detecting the blood by a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the test person, and then determining the blood sodium 24 specific activity; based on the blood sodium 24 specific activity and the pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient, obtaining the neutron dose of the test person; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the physical data and irradiation data of the test person using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry. Specifically, the specific implementation method when the computer program is executed by the processor can refer to the description of the relevant steps in the neutron dose assessment method based on the blood sodium 24 specific activity in the embodiment, which will not be repeated here.

[0137] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation.

[0138] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0139] In addition, each functional module in each embodiment of the present invention may be integrated into one processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0140] It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0141] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, so it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any attached figure mark in the claims should not be regarded as limiting the claims involved.

[0142] The blockchain referred to in this invention is a new application mode of computer technologies such as distributed data storage, peer-to-peer transmission, consensus mechanism, encryption algorithm, etc. Blockchain is essentially a decentralized database, a string of data blocks generated by cryptographic methods. Each data block contains a batch of network transaction information, which is used to verify the validity of its information (anti-counterfeiting) and generate the next block. Blockchain can include the underlying blockchain platform, platform product service layer, and application service layer.

[0143] In addition, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices stated in a device claim can also be implemented by one unit or device through software or hardware. The second and other words are used to indicate names, but not to indicate any particular order.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A neutron dose assessment method based on blood sodium 24 specific activity, characterized in that the method include: Obtaining blood and physical data of the tested person; wherein the physical data includes the height and weight of the tested person; The blood is tested by a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the tested person, and then the blood sodium 24 specific activity is determined; this is achieved by the following formula: Wherein, X0 is the characteristic gamma ray count of sodium 24 in the blood sample of the tested person obtained by testing the blood with a neutron dosimeter, and λ is the decay constant of sodium 24, λ≈1.2836×10 -5 ; ε is the detection efficiency of the detector, ε≈12.34%; I is the branching ratio of the characteristic gamma ray of sodium 24, I≈100%; t is the measurement time, t=600s, the specific activity of sodium 24 A S , the unit is Bq / g; Based on the blood sodium 24 specific activity and the pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient, the neutron dose of the tested person is obtained; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the body data and irradiation data of the tested person using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry; and the blood sodium 24 specific activity after sodium content correction is obtained according to the blood sodium 24 specific activity; The method further includes performing time difference correction on the neutron dose of the tested person, and obtaining the neutron dose G of the tested person after time difference correction by the following formula: s ; G s =A c ×L n (E,K)×T c Among them, T c is the time correction factor; L n (E, K) is the blood sodium 24 specific activity-neutron dose conversion coefficient; A C The specific activity of blood sodium 24 after correction for sodium content; T = 14.12h, t0-t1 is the time difference between the occurrence of neutron irradiation and the measurement of sodium 24 activity in the blood of the tested person; E is the neutron energy; K is the neutron irradiation method; It also includes the specific activity of blood sodium 24A S Perform individual blood sodium content correction and obtain the blood sodium 24 specific activity A after sodium content correction using the following formula C ; A c =A s ×S n / S s Among them, S n is the blood sodium content value used in the human digital model corresponding to the preset height and weight, S s It is the actual blood sodium content of the tested person.

2. The neutron dose assessment method based on blood sodium 24 specific activity according to claim 1, characterized in that: The method for obtaining the blood sodium 24 specific activity-neutron dose conversion coefficient comprises: Using the preset human tomographic image data sets corresponding to different heights and weights, digital human models corresponding to different heights and weights are established; Obtain the number of pixels and density value of each organ tissue of the human digital model corresponding to the preset height and weight, and then obtain the blood tissue quality; Based on blood tissue 23 The Na mass percentage, blood tissue mass and Avogadro constant are used to obtain the blood tissue mass in the human digital model corresponding to the preset height and weight. 23 The number of Na atoms; The particle transport simulation program was used to simulate the human body digital model with preset height and weight, based on the blood tissue quality and blood tissue 23 The number of Na atoms obtains the neutron dose and blood sodium 24 specific activity corresponding to the preset neutron energy and neutron irradiation geometry; According to the neutron dose and the blood sodium 24 specific activity, a blood sodium 24 specific activity-neutron dose conversion coefficient is obtained.

3. The neutron dose assessment method based on blood sodium 24 specific activity according to claim 1, characterized in that: The neutron dose G corresponding to the preset neutron energy and neutron irradiation geometry is obtained through the human digital model corresponding to the preset height and weight. n (E, K) is achieved by the following formula: Among them, D n,t (E,K) represents a human digital model H with a single neutron of neutron energy E and irradiation method K. n (h,w) Organ O n,t The deposited energy in J; M n,t For organ O n,t The mass of , in g, K∈(LLAT, RLAT, AP, PA, ISO, ROT).

4. The neutron dose assessment method based on blood sodium 24 specific activity according to claim 1, characterized in that: Using the particle transport simulation program, the human digital model corresponding to the preset height and weight is used to obtain the blood sodium 24 specific activity A corresponding to the preset neutron energy and neutron irradiation geometry. n The method of (E, K) comprises: A n (E, K)=F n (E,K,ε)×σ(ε)×B n (h,w) / M n,1 Among them, F n (E, K, ε) represents the human body digital model H n (h,w) is the neutron fluence in the blood under the irradiation condition of a single neutron with energy E and irradiation geometry K, ε is the neutron energy reaching the blood after slowing down; σ(ε) is the difference between the neutron with energy ε and the blood 23 The cross section of Na capture reaction; B n (h,w) represents the human body digital model H n The number of atoms of blood sodium 23 in (h,w); M n,1 Human body digital model H n (h,w) blood tissue mass.

5. A neutron dose assessment device based on blood sodium 24 specific activity, characterized in that: The device comprises, A test data acquisition unit, used to acquire blood and body data of the test person; wherein the body data includes the height and weight of the test person; The specific activity measurement unit is used to detect the blood through a neutron dosimeter to obtain the sodium 24 characteristic gamma ray count in the blood sample of the tested person, and then determine the blood sodium 24 specific activity; it is achieved by the following formula: Wherein, X0 is the characteristic gamma ray count of sodium 24 in the blood sample of the tested person obtained by testing the blood with a neutron dosimeter, and λ is the decay constant of sodium 24, λ≈1.2836×10 -5 ; ε is the detection efficiency of the detector, ε≈12.34%; I is the branching ratio of the characteristic gamma ray of sodium 24, I≈100%; t is the measurement time, t=600s, the specific activity of sodium 24 A S , the unit is Bq / g; A neutron dose acquisition unit is used to obtain the neutron dose of the subject based on the blood sodium 24 specific activity and the pre-acquired blood sodium 24 specific activity-neutron dose conversion coefficient; wherein the blood sodium 24 specific activity-neutron dose conversion coefficient is obtained according to the body data and irradiation data of the subject using a human body digital model; the irradiation data includes neutron energy and neutron irradiation geometry; and the blood sodium 24 specific activity after sodium content correction is obtained according to the blood sodium 24 specific activity. The method further includes performing time difference correction on the neutron dose of the tested person, and obtaining the neutron dose G of the tested person after time difference correction by the following formula: s ; G s =A c ×L n (E,K)×T c Among them, T c is the time correction factor; L n (E, K) is the blood sodium 24 specific activity-neutron dose conversion coefficient; A C The specific activity of blood sodium 24 after correction for sodium content; T = 14.12h, t0-t1 is the time difference between the occurrence of neutron irradiation and the measurement of sodium 24 activity in the blood of the tested person; E is the neutron energy; K is the neutron irradiation method; It also includes the specific activity of blood sodium 24A S Perform individual blood sodium content correction and obtain the blood sodium 24 specific activity A after sodium content correction using the following formula C ; A c =A s ×S n / S s Among them, S n is the blood sodium content value used in the human digital model corresponding to the preset height and weight, S s It is the actual blood sodium content of the tested person.

6. An electronic device, characterized in that: The electronic device comprises: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the steps of the neutron dose assessment method based on blood sodium 24 specific activity as claimed in any one of claims 1 to 4.

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